"...has not concluded whether or not the victims are legal citizens."
Whether or not, indeed. You don't need "or not," after whether. Should read, "has not concluded whether the victims are legal citizens," or preferably, and simpler, "...if the victims are legal citizens." Why are borderline illiterates reporting on supposedly legit news sites?
Excuse the hell out of me, but there is no such thing as an ‘Illegal Citizen’. There are legal and illegal immigrants. There are legal and illegal visitors. But there ain’t no ‘illegal citizens’
Stupid, stupid Reporter. Ignorance can be cured but stupidity is terminal.